In the 70s, as an ATCO at Eastern Radar, I was tasked with giving lectures to new USAF crews in the UK at LKH, BTW and UPH. I thing I still have the slides! Part of the emphasis was on using the proper terms (MAYDAY or PAN), explaining the UK D&D organisation and reassuring them there was no fee. Interesting to see that 50 years later US Mil continues to plough its own furrow (literally), regardless.
Perhaps my best/worst case was in ‘68, with a TF-100 pilot who had ejected ... and while floating down into the North Sea east of Strubby used his PLB to transmit on 243.0 and say “This is Wiggins, anybody there?”. He was triangulated and recovered by SAR from Coltishall ... sadly his colleague was never found.